Three-dimensional light-field microendoscopy with a grin lens array

Abstract

An optical microendoscopy includes an endoscopic probe that has a plurality of integrated fiber optics for uniform illumination and an array of gradient index (GRIN) lenses. The GRIN lenses are configured to capture a reflected light field from one or more on-axis sampling of the reflected light field and two or more off-axis sampling of the reflected light field

What is claimed is: 
     
         1 . An optical microendoscopy system, comprising:
 an endoscopic probe, the probe having a plurality of integrated fiber optics for uniform illumination and an array of gradient index (GRIN) lenses configured to capture a reflected light field from one or more on-axis sampling of the reflected light field and two or more off-axis sampling of the reflected light field.   
     
     
         2 . The optical microendoscopy system of  claim 1 , wherein the captured reflected light field comprises 6 off-axis samples. 
     
     
         3 . The optical microendoscopy system of  claim 1 , wherein the plurality of integrated fiber optics comprises 3 or more fibers embedded within an endoscopic probe core, each having an illumination output. 
     
     
         4 . The optical microendoscopy system of  claim 1 , wherein each of the fiber optics comprise an illumination output at an end of the endoscopic probe, wherein the illumination outputs are distributed equally at the end of the endoscopic probe. 
     
     
         5 . The optical microendoscopy system of  claim 1 , wherein the GRIN lens array comprises 6 GRIN lenses. 
     
     
         6 . The optical microendoscopy system of  claim 5 , wherein the 6 GRIN lenses are positioned in a hexagonal array at an end of the endoscopic probe, and wherein the system further includes a seventh GRIN lens at a center of the hexagonal array at the end of the endoscopic probe. 
     
     
         7 . (canceled) 
     
     
         8 . The optical microendoscopy system of  claim 6 , further comprising an illumination output of one of the integrated fiber optics at a center of the hexagonal array at the end of the endoscopic probe. 
     
     
         9 . The optical microendoscopy system of  claim 1 , wherein GRIN lenses of the GRIN lens array alternate with illumination outputs of individual ones of the integrated fiber optic at an end of the endoscopic probe. 
     
     
         10 . The optical microendoscopy system of  claim 1 , further comprising:
 an image processing unit configured to receive the reflected light field from the endoscopic probe to reconstruct an image using a ray-optics reconstruction operation.   
     
     
         11 . The optical microendoscopy system of  claim 10 , wherein the image processing unit is configured to employ point-spread function (PSF) calibration in a ray-optics reconstruction operation. 
     
     
         12 . The optical microendoscopy system of  claim 11 , wherein the point-spread function (PSF) calibration involves fitting an experimental depth-dependent magnification function M(z) with a ray-optics model of magnification. 
     
     
         13 . The optical microendoscopy system of  claim 1 , wherein a first subset of the GRIN lenses in the array comprises a first property and wherein a second subset of the GRIN lenses in the array comprise a second property different from the first. 
     
     
         14 . The optical microendoscopy system of  claim 13 , wherein the first property is a first polarization and the second property is a second polarization. 
     
     
         15 . The optical microendoscopy system of  claim 13 , further comprising a third subset of GRIN lenses comprise a third property different from the first property and the second property. 
     
     
         16 . The optical microendoscopy system of  claim 15 , wherein the first property, the second property, and the third property are selected from polarization, fluorescence in addition to the bright field, wavelength, and time-gated light. 
     
     
         17 . The optical microendoscopy system of  claim 1 , wherein the integrated fiber optics comprises LED light sources. 
     
     
         18 . The optical microendoscopy system of  claim 1 , wherein the endoscopic probe comprises a Hopkins rod lens or a gradient index relay. 
     
     
         19 . (canceled) 
     
     
         20 . The optical microendoscopy system of  claim 1 , further comprising a laser light source at an end of the endoscopic probe and a camera for receiving reflected laser light. 
     
     
         21 . (canceled) 
     
     
         22 . A method of operating an optical microendoscopy system, the method comprising:
 providing illumination from an end of an endoscopic probe, the endoscopic probe having a plurality of integrated fiber optic illumination sources for uniform illumination;   capturing a reflected light field, for light-field imaging, through an array of gradient index (GRIN) lenses, including (i) one or more on-axis sampling of the reflected light field and (ii) two or more off-axis sampling of the reflected light field; and   reconstructing an image via a reconstruction algorithm using (i) the one or more on-axis sampling of the reflected light field and (ii) the two or more off-axis sampling of the reflected light field.   
     
     
         23 .- 35 . (canceled) 
     
     
         36 . An endoscopic probe, comprising:
 a plurality of integrated fiber optics for uniform illumination and an array of gradient index (GRIN) lenses configured to capture a reflected light field from one or more on-axis sampling of the reflected light field and two or more off-axis sampling of the reflected light field